Title of Invention

DWELL CREATING DEVICE FOR MULTIPLE PAIR OF CROSS SEALING JAWS OF HORIZONTAL FLOW WRAP MACHINE

Abstract

A dwell creating device for multiple pair of cross sealing jaws (1) for use in horizontal flow wrap machine, said dwell creating device comprising: an eccentric dwell wheel (2) provided with one or more slots and being mounted on a dwell flat (3) through a drive sprocket (4); a cam follower (5) being fitted/connected through the slots to the eccentric dwell wheel (2); a lower jaw gear (6) being connected to the cam follower (5) optionally through a timing mechanism such as herein described and an upper jaw gear (7) being coupled to the lower jaw gear (6) through a coupling means such as herein described, and said lower jaw gear (6) being coupled to a lower jaw shaft (8) mounted with one or more lower jaws and said upper jaw gear (7) being coupled to a upper jaw shaft (9) mounted with one or more upper jaws.

Full Text

FORM 2 THE PATENTS ACT, 1970 (39 of 1970) PROVISIONAL SPECIFICATION (See section 10) "DWELL CREATING DEVICE FOR MULTIPLE PAIR OF CROSS SEALING JAWS OF HORIZONTAL FLOW WRAP MACHINE" MULTI PACK SYSTEMS Paqtriot Complex, Ellora Park, Baroda, Gujarat 390 007, India. The following specification describes the nature of the invention. DWELL CREATING DEVICE FOR MULTIPLE PAIR OF CROSS SEALING JAWS OF HORIZONTAL FLOW WRAP MACHINE FIELD OF THE INVENTION Dwell creating device for multiple pair of cross sealing jaws of Horizontal Flow Wrap Machine. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS In the drawings accompanying the specification, Figure 1 represents the prior art mechanism for twin jaws dwell arrangement with eccentric gear. Figure 2 represents the prior art mechanism for twin jaws dwell arrangement with connecting link and gear. Figure 3 represents the newly developed mechanism for twin jaw dwell arrangement with eccentric dwell wheel and gear train. Figure 4 represents the newly developed mechanism for twin jaw dwell arrangement with eccentric dwell wheel and driven by timing belt. Figure 5 describes the method for preventing inertia with dwell disc. Figure 6 represents the relationship of maximum and minimum packet length with jaw. BACKGROUND AND PRIOR ART DESCRIPTION The purpose of dwell creating mechanism is to rotate cross sealing jaws at variable speed to achieve the following: a) To match average wrapper speed during the point of contact; b) To give maximum dwell time at Zero position i.e. when both the jaws are perfectly c) To provide necessary inertia to both the jaw shafts immediately after cutting of the packet (this is illustrated in Figure 5 (Sketch A)); 2 d) To act as a fly wheel releasing high energy during half cycle of the jaws (as illustrated in Figure 5 (Sketch A)); There are two methods available at present for creating dwell in multiple jaws which are described. 1. Existing mechanism for creating dwell with eccentric gear: A mechanism for creating dwell using eccentric gear is shown in Figure 1. The gear which creates the eccentricity is mounted on input driving shaft with a sliding eccentric piece and screw for adjusting eccentricity of sliding block. When the screw is rotated sliding blocks creates the eccentricity between centre line of input drive shaft and the input gear. When the input gear rotates eccentric with respect to input shaft, the driving radius increases when the gear center falls away from mating gear causing decrease in the angular velocity of the mating gear. Similarly when the gear centre falls near to the mating gear, the driving radius decreases causing increase in the angular velocity of the mating gear. So in one rotation, it creates the dwell action by causing increase and decrease of peripheral velocity. This mechanism is illustrated in Figure 1. 2. Existing mechanism for creating dwell with connecting link and gear: A mechanism for creating dwell using connecting link and gear is shown in Figure 2. Here lower jaw gear is connected with drive sprocket through connecting link which form a four bar crank chain mechanism. The eccentricity between drive sprocket and tower jaw gear is created by lowering the dwell flat. Because of eccentric position of drive sprocket, it continuously changes the crank radius creating the variable peripheral velocity of lower jaw gear. This mechanism is illustrated in Figure 2. 3 OBJECTS OF THE PRESENT INVENTION The main object of the present invention is to provide a new mechanism wherein the dwell created through eccentric wheel is transferred to cross sealing jaws. Another object of the present invention is to provide a gear train mechanism for transferring the dwell created by the eccentric wheel to the cross sealing jaws. Yet another object of the present invention is to provide a timing belt mechanism for transferring the dwell created by the eccentric wheel to the cross sealing jaws. Still another object of the present invention is to provide a duplex chain mechanism for transferring the dwell created by the eccentric wheel to the cross sealing jaws. DESCRIPTION OF THE PRESENT INVENTION The lower jaw gear is connected/driven by the cam follower mounted on it. The cam follower is guided in the slot of eccentric dwell wheel which is connected on the drive sprocket. When the dwell flat is taken down, it creates eccentricity between lower jaw gear and eccentric dwell wheel. This mechanism is illustrated in Figures 3 and 4. ADVANTAGE OF NEW METHOD (a) The same dwelling mechanism can be used from single pair to multiple pair of jaws with the help of change gears. This gives very high flexibility of the machine in terms of total packet length, which can be accommodated on this machine. This is elaborated further in Figure 6 (Sketch - B). (b) The inertia storing/releasing system provide by the disc reduces the vibration in the up stream and down stream mechanism resulting into smoother machine operation. This allows the machine to run at higher speeds as given in the following comparison table: 4 After dead center cutting position, due to spring force the jaws has a tendency to travel at high speed resulting into rubbing of the cutting knife edge with the Anvil surface. This reduces the life of knife and also sometime tries to pull the succeeding packet. In case of our new method, jaws do not travel unrestricted against a torque developed by the compressed spring as the torque is absorbed by the inertia of dwell disc. This is illustrated in Figure 5 (Sketch A). Dated this 13th day of January, 2003. G. DEEPAK SRTNIWAS OF KUMARAN & SAGAR AGENT FOR THE APPLICANTS 5 We Claim: 1. A dwell creating device for multiple pair of cross sealing jaws (1) for use in horizontal flow wrap machine, said dwell creating device comprising: an eccentric dwell wheel (2) provided with one or more slots and being mounted on a dwell flat (3) through a drive sprocket (4); a cam follower (5) being fitted / connected through the slots to the eccentric dwell wheel (2); a lower jaw gear (6) being connected to the cam follower (5) optionally through a timing mechanism such as herein described and an upper jaw gear (7) being coupled to the lower jaw gear (6) through a coupling means such as herein described, and said lower jaw gear (6) being coupled to a lower jaw shaft (8) mounted with one or more lower jaws and said upper jaw gear (7 )being coupled to a upper jaw shaft (9) mounted with one or more upper jaws. 2. A dwell creating device as claimed in claim 1, wherein the eccentric dwell wheel (2) is provided with a single slot at a periphery of the wheel. 3. A dwell creating device as claimed in claim 1, wherein the dwell flat (3) is movable in a vertical direction for creating dwell. 4. A dwell creating device as claimed in claim 1, wherein the dwell flat (3) is moved in the vertical direction by means of a motor. 5. A dwell creating device as claimed in claim 1, wherein the lower jaw gear (6) is either coupled directly to the cam follower (5) or through a timing mechanism to the cam follower (5). 6. A dwell creating device as claimed in claim 5, wherein the timing mechanism includes a timing pulley (10) mounted with a timing belt (11), wherein the timing pulley (10) is coupled to the cam follower (5) and the timing belt (11) is coupled to the lower jaw gear (6). 8 7. A dwell creating device as claimed in claim 1, wherein a set of dwell discs (12) are optionally provided to the upper (9) and lower jaw shafts (8) for providing 8. A dwell creating device as claimed in claim 1, wherein the lower jaw shaft (8) is mounted with two lower jaws and said upper jaw shaft (9) is mounted with two upper jaws. 9. A dwell creating device as claimed in claim 1, wherein the distance between the lower jaw shaft (8) and the upper jaw shaft (9) is preferably in the range of 100- 10. A dwell creating device as claimed in claim 1, wherein the packet length obtained when the upper (9) and the lower jaw shafts (8) are mounted with a single jaw is in the range of 95 to 330 mm. 11. A dwell creating device as claimed in claim 1, wherein the packet length obtained when the upper (9) and the lower jaw shafts (8) are mounted with a two jaw is in the range of 65 to 165 mm. 12. A dwell creating device substantially as herein described with reference to the accompanying drawings. Dated this 13lh day of January, 2003. OMANA RAMAKRISHNAN OF K & S PARTNERS AGENT FOR THE APPLICANT

Documents:

35-mum-2003-abstract (4-10-2005).doc

35-mum-2003-abstract (4-10-2005).pdf

35-mum-2003-cancelled pages(13-4-2004).pdf

35-mum-2003-claims(granted)-(13-1-2003).doc

35-mum-2003-claims(granted)-(13-1-2003).pdf

35-mum-2003-correspondence 1(13-3-2007).pdf

35-mum-2003-correspondence 2(5-12-2005).pdf

35-mum-2003-correspondence(ipo)-(28-10-2004).pdf

35-mum-2003-drawing(13-1-2003).pdf

35-mum-2003-form 1(13-1-2003).pdf

35-mum-2003-form 1(3-4-2003).pdf

35-mum-2003-form 13(4-10-2005).pdf

35-mum-2003-form 19(21-8-2004).pdf

35-mum-2003-form 2(granted)-(13-1-2003).doc

35-mum-2003-form 2(granted)-(13-1-2003).pdf

35-mum-2003-form 26(27-10-2005).pdf

35-mum-2003-form 3(13-1-2003).pdf

35-mum-2003-form 3(4-10-2005).pdf

35-mum-2003-form 4(13-4-2004).pdf

35-mum-2003-form 5(13-1-2003).pdf

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